The aim of this prospective, randomized, multicenter trial is to compare the rates of post-ESP pancreatitis in patients who did or did not prophylactic pancreatic duct stent placement. Consecutive patients who were to undergo ESP were to randomized to pancreatic duct stent placement group (stent group) after endoscopic snare papillectomy or to no pancreatic duct stent placement group (no stent group).